GB1256904A - - Google Patents

Abstract

1,256,904. Coated mating surfaces. OAKLAND CORP. 24 Feb., 1969 [24 April, 1968], No. 9797/69. Heading B2E. A metal member for use with a mating part, e.g. a screw or bolt is at least partially coated on the surface which is to slide relative to the mating part with a plasticised silicone resin wherein the outer surface of the coating is dry and non-tacky and the interior of the coating is in a highly viscous condition and is capable of flow under the internal shear stresses caused by relative movement of the member and the mating part up to a limiting shear at which flow is resisted. The resin may contain methyl and phenyl substituents, the degree of crosslinking being such that the resin contains Si atoms with two methyl or phenyl substituents and Si atoms with one methyl or phenyl substituent. The coating may be applied as a solution or suspension of the resin and plasticiser in a carrier liquid. The carrier liquid, which may be acetone or toluene, may be evaporated by radiant heat although in the case of toluene it is preferred to leave a residue to act as a plasticiser. Nylon or epoxy resin may be included in the composition. The coating may be applied by spraying, dipping or printing. In one embodiment the bolt is inserted in a hole in a belt, or is gripped between two parallel belts, so that the thread is suspended vertically and is conveyed through a spray or bath of the resin. When two belts are used they preferably travel at different speeds in order to rotate the bolt. In another embodiment, the threads are fed between the nip of a pair of rollers whose lower portions are dipped in a bath of the resin.